Unlocking the Photocatalytic Oxidative Dehydrogenative Performance of a Polyoxomolybdate: The Cross-Coupling of P(O)H Compounds and Thiols

We disclose herein the oxidative dehydrogenation performance of a Lindquist-type polyoxomolybdate, [N(C4H9)4]2[Mo6O19], with irradiation with visible light. The formulated inorganic molecular Mo6 photocatalyst can facilitate, with high efficiency, the cross-dehydrogenative coupling of P(O)H compounds and thiols in water with ambient oxygen as the oxidant. Moreover, a gram-scale reaction can smoothly proceed under a simple, low catalyst loading system with high turnover numbers. This catalyst exhibited good stability and reusability after at least six turns of the reaction and even showed satisfactory photocatalytic activity under sunlight irradiation. Bypassing using complicated organic ligands and noble metal-based photosensitizers, this easily available, cheap, and recyclable hexamolybdate represents an alternative photocatalyst to realize oxidative dehydrogenative processes under metal-, base-, and external-oxidant-free conditions.